Fumonisin B(1): a neurotoxic mycotoxin.

Fumonisin B(1) (FB(1)) is a mycotoxin produced by Fusarium spp. moulds that contaminate crop, predominantly maize, all around the world. More than 15 types of fumonisins have been indentified so far, but FB(1) is the most abundant and toxicologically the most significant one. FB(1) has a wide range of toxic effects, depending on animal species. In horses FB(1) causes equine leukoencephalomalacia (ELEM), in pigs pulmonary oedema and in experimental rodents nephrotoxicity and hepatotoxicity. In humans exposure to FB(1) is linked with higher incidence of primary liver cancer and oesophageal cancer, which are frequent in certain regions of the world (such as Transkei region in South Africa) where maize is staple food. The occurrence of neural tube defect in children in some countries of Central America (such as Mexico and Honduras) is connected with the consumption of FB(1)-contaminated maize-based food. However, possible involvement of FB(1) in the development of human diseases is not clear. Nevertheless, the International Agency for Research on Cancer (IARC) has classified FB(1) as a possible carcinogen to humans (group 2B). FB(1) is a causative agent of ELEM, a brain disorder in equines, indicating that brain is a target organ of FB(1) toxicity. Several studies on experimental animals or on cell cultures of neural origin have established that FB(1) has a neurodegenerative potential, although the mechanism of its neurotoxicity is still vague. The aim of this article is to give an overview of available literature on FB(1) neurotoxicity and involved mechanisms, and to offer a new perspective for future studies.